A Prudent-Precedence Concurrency Control Protocol for High Data Contention Database Enviornments

摘要

In this paper, we propose a concurrency control protocol, called the Prudent-Precedence ConcurrencyControl (PPCC) protocol, for high data contention database environments. PPCC is prudently moreaggressive in permitting more serializable schedules than two-phase locking. It maintains a restrictedprecedence among conflicting transactions and commits the transactions according to the serializationorder established in the executions. A detailed simulation model has been constructed and extensiveexperiments have been conducted to evaluate the performance of the proposed approach. The resultsdemonstrate that the proposed algorithm outperforms the two-phase locking and optimistic concurrencycontrol in all ranges of system workload.